In order to achieve further miniaturization of semiconductor devices, a critical dimension of the devices has to be more downsized than that achieved by the existing micro fabrication process using lithography technology. To achieve this, EUV (Extreme Ultraviolet) lithography, a next generation lithography technology, has been developed. In the EUV lithography, a very short wavelength of a light source, for example, 13.5 nm, is used. Because of this, in EUV lithography, there are technological obstacles for mass production due to an extremely shorter wavelength of a light source than in a conventional UV light source, for example, problems of a long lithography time period and the like. Accordingly, development of a method for manufacturing a more miniaturized device has been desired without waiting for the advancement in the development of the next generation lithography technology of EUV lithography technology.
Therefore, Patent Document 1 focuses on a self-assembled block copolymer (BCP: block copolymer), which is one of many self-assembled materials that spontaneously organize an ordered pattern internally. More specifically, a block copolymer layer containing at least two polymer block components A and B that do not mix with each other is applied to an underlayer film. After that, the polymer block components A and B spontaneously separate in phase from each other by being annealed. An ordered pattern constituted of nano-size structure units obtained from this process is effective to provide a further miniaturized device.
Patent Document 2 proposes a patterning process of the block copolymer as a method for forming a via-hole having a proper and uniform critical dimension (CD: Critical Dimension) and a narrower pitch.
The dimension of the structure unit formed by patterning the block copolymer is within a scope of 10 nm, which is difficult to be implemented by the conventional lithography technology.
Furthermore, the structure unit formed by the block copolymer adjusts to conventional semiconductor, optical and magnetic processes, and therefore can be incorporated into semiconductor, optical and magnetic devices.